function Person() {
  this.name = 'nihao'
  this.play = [1, 2, 3]

}
Person.prototype.study = function () {
  console.log(111)
}

function Child() {
  Person.call(this)
}
Child.prototype = new Person()

let p1 = new Child()

console.log(p1.name)
p1.study()

